The invention relates to a panoramic night vision goggle system having at least an inner and outer optical channel per monocular subassembly and having a modified eyepiece that enables an improved field of view for at least the inner optical channel.
Panoramic Night Vision Goggle (PNVG) systems are known. One type of PNVG comprises two monocular subassemblies, each containing two image intensifier tubes. The subassemblies are mounted on a bridge assembly. Each subassembly has an inner tube and an outer tube. In one configuration, the inner tubes each have an optical axis that is substantially coaxial with one of the user""s optical axes and have a partially overlapping field of view (FOV) (e.g., each may have approximately a 40 degree FOV or any other FOV). The outer tubes each have an optical axis that is angled with respect to the user""s optical axes so that peripheral vision is used to see a greater field of view.
At least some prior systems design a monocular subassembly eyepiece to have two lens elements, both of which are ground relatively flat on the sides at which they contact. For example, FIG. 1 shows an existing eyepiece configuration with anouter channel eyepiece element 100 and an inner eyepiece element 102. Elements 100 and 102 contact each other along their respective flat sides as indicated at 104. This design has various drawbacks, one of which is that it decreases the field of view for the inner eyepiece element, which is typically the element through which the major viewing activity takes place. These and other drawbacks exist.
An object of the invention is to overcome these and other drawbacks.
Another object of the present invention is to provide a PNVG system with one or monocular subassemblies each containing at least an inner optical channel and an outer optical channel that combine to form a single image and where the monocular subassembly comprises a combined eyepiece characterized by an outer eyepiece element being shaped to accommodate the profile of a substantially unmodified inner eyepiece element.
According to one embodiment, the inner eyepiece is generally circular and the outer eyepiece is generally circular except for the portion of an edge that abuts the inner eyepiece, such portion being complementary shaped with respect to the abutting portion of the inner eyepiece.
According to one embodiment of the invention, the monocular subassembly may comprise a combined eyepiece that allows the inner channel eyepiece element to remain whole. A portion of the outer eyepiece element may be cut in a circular fashion to accommodate the inner eyepiece and to allow for the perceived complete overlap of the image provided by both inner channels. Other configurations and geometries may be used. Designing the combined eyepiece in this way can improve the image resolution over the field of view.